NEW YORK — The Knicks haven't been able to escape the problem all season.

One bad quarter has repeatedly cost them.

The Knicks on Monday got off to a good start, held a seven-point lead at halftime and then collapsed in the third quarter as the Phoenix Suns ran away with the game.

A potential victory on the second half of a back-to-back fell apart and turned into an embarrassing defeat.

The Knicks surrendered 41 third-quarter points as Phoenix won in a blowout, 128-110, at Madison Square Garden.

"We fall into the same thing: One quarter," Knicks coach David Fizdale said. "You got a deflated quarter where we don’t do the same things that we do for the other three quarters and it always comes back to bite us."

It was the third straight victory for the Suns (7-24), another young team that will almost certainly be joining the Knicks in the lottery.

Once Phoenix took a double-digit lead, the Knicks couldn't get enough of the defensive stops they needed to make a comeback.

Devin Booker finished with 38 points for Phoenix, while T.J. Warren had 26.

One bright spot for the Knicks was Emmanuel Mudiay's performance. He finished with 32 points, six rebounds and six assists.

The Knicks have been hit hard by injuries lately, and were already without Allonzo Trier (strained hamstring), Mitchell Robinson (sprained left ankle) and Damyean Dotson (shoulder).

Then just more than an hour before the game started, the Knicks (9-23) announced they were also without Tim Hardaway Jr. because of a sore right heel.

Fizdale said Hardaway's heel was bothering him after Sunday's loss to Indiana, so the team decided to rest him for the second half of the back to back. The coach said he believes Hardaway will be available Wednesday against the Sixers, but wasn't certain.

This was the first time the Knicks went up against No. 1 overall pick Deandre Ayton, who finished with 21 points and 13 rebounds.

It was also the first time they saw rookie wing Mikal Bridges, who the Suns drafted 10th overall, one spot after the Knicks selected Kevin Knox.

Like Knox, Bridges has also had an up-and-down rookie season.

But Knox outplayed Bridges on Monday, scoring 13 of his 17 points in the first half to help get the Knicks a 66-59 lead by halftime.

Bridges, who had seven points, didn't score until midway through the second quarter when he had three straight baskets in transition to cut the Suns' deficit to three points.

As well as the Knicks played in the first half, they couldn't keep that momentum going in the third quarter.

Not even close.

"I’m the one that’s sitting up there trying to stop the bleeding with timeouts and things like that," Fizdale said. "But you know, I’ve got to keep it in mind: This is our painful path to growth. For me I just have to look at it from the perspective, how do I make us better and not get too caught up emotionally in what’s going wrong. How do I fix it."

The score was tied at 4:49 of the period when Mudiay made a layup, but Phoenix started running away with the game.

"We just stopped competing defensively," Knox said. "Offensively the ball stopped. We weren’t moving it like we were in the first half."

The Suns, who shot 52.2 percent from the field, went on a 21-4 run to take a 100-83 run by the end of the quarter. They outscored the Knicks 41-17 in the period.

It was Phoenix's game from there.

"Our defensive intensity just went down," Mudiay said. "Think they kind of ramped it up a little bit. We kind of folded into what they wanted us to do. The defense is really what got us."